What does the DP System use to calculate weighting (or confidence) for each Position Reference System?

The Dynamic Positioning (DP) System calculates weighting, or confidence, for each Position Reference System based on the relative spread of fixes. This approach allows the DP system to assess how consistent and accurate the position readings are from different reference systems. When the fixes from various systems are closely grouped together, the DP system can assign a higher confidence level to those readings, indicating that the position is more reliably determined.

The relative spread of fixes provides valuable insight into the reliability of the positioning data. If the fixes show a wide spread, it suggests a lower level of confidence because it indicates potential errors or inconsistencies in the positioning data. On the other hand, a tight cluster of fixes would lead to the system assigning higher confidence.

Using historical data from previous voyages may provide context but does not directly factor into real-time weighting for position references. The average position error is more about a general assessment of positioning accuracy rather than the relative confidence of individual systems. Lastly, while feedback from the crew can be valuable, it does not directly contribute to the quantitative calculation of system weighting in the same way the relative spread does. Thus, the approach rooted in the relative spread of fixes is essential for maintaining the integrity and accuracy of DP operations.